Hammer



FIG. 1 is a perspective view of a hammer, showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The dashed lines depict environmental subject matter, are for illustration only and form no part of the claimed design. The dash-dot lines depict boundaries between the claimed part and non-claimed part and form no part of the claimed design. 

CLAIM The ornamental design for a hammer, as shown and described. 